EDIT:
So far I've burned 25 games on an external (USB) LITE-ON 16xDVDRW SOHW-1673S at 6x and haven't gotten one DRE yet.
The only problems I've faced is with NTSC games, like Elebits and Wing Island. Sometimes when I insert Elebits a black screen with a little paragraph of text saying the disc is broken or whatever but then I just reboot the console and it works fine.